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Modelling of Dynamic Properties of Gearboxes Using Virtual Prototypes
Otipka, Václav ; Trochta,, Miroslav (referee) ; Žlábek,, Pavel (referee) ; Píštěk, Václav (advisor)
Transmissions are very widespread across all categories of technical products. Their role is irreplaceable, however, their operation is always associated with the generation of significant vibration and noise, which is also considered one of the main disadvantages, which manifests itself especially in heavily loaded transmissions and represents a disadvantage mainly in terms of product competitiveness and possible legislation problems. This problem can be solved in part through sophisticated transmission optimization, which, however, requires considerable effort, time, and money. This is the main reason why there is constant pressure to find efficient solutions for optimization and why the scientific community is still paying considerable attention to this area. At present, a combination of computational and experimental approaches is used for overall optimization in this area. This dissertation is focused on the prediction and understanding of the transmission dynamic behaviour, which requires the construction of an advanced, complex computational model. Computational modelling is supported by a number of partial technical experiments, which are used to validate the results.
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Growth of nanoparticles in liquid medium using magnetron sputtering technique
Kučera, Josef ; Yakovlev, Yurii (advisor) ; Khalakhan, Ivan (referee)
Title: Growth of nanoparticles in liquid medium using magnetron sputtering technique Author: Josef Kučera Department: Department of Surface and Plasma Science Supervisor: Mgr. Yurii Yakovlev, Ph.D., Department of Surface and Plasma Science Abstract: This thesis investigates the preparation of platinum and platinum-ruthenium alloy nanoparticles using magnetron sputtering method on a liquid substrate. Polypropylene glycol with three different molecular weights of 425, 1000, and 4000 was chosen as the liquid substrate. The influence of the different viscosities of these substrates on the size and morphology of the nanoparticles produced in the magnetron was investigated. Dynamic light scattering and transmission electron microscopy methods were used to determine the size of the nanoparticles. Furthermore, the catalytic activity of the produced nanoparticles in an alkaline environment was investigated using the rotating disk electrode technique. Keywords: Nanoparticles, Magnetron Sputtering, Polypropylene glycol, Hydrogen Fuel Cells, Water Electrolyzers, Hydrogen oxidation/reduction reactions.
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Role of the SMN complex in snRNP biogenesis
Hanušková, Klára ; Staněk, David (advisor) ; Šubrtová, Adriána (referee)
Small nuclear ribonucleoprotein particles (snRNPs) are an essential component of the spliceosome, a dynamic protein complex that mediates RNA splicing. These particles are composed of a single small nuclear RNA, from which they take their name, a ring of seven Sm or LSm proteins and other accessory proteins. All snRNPs undergo a complex maturation pathway, taking place in the nucleus and cytoplasm of the cell. One important factor in snRNP biogenesis is the SMN complex, which is composed of the SMN, Gemin2-8 and Unrip proteins. Its most important function is to mediate the assembly of the Sm core domain in the cytoplasm of the cell, with the help of the PRMT5 complex. Furthermore, the SMN complex is also involved in snRNA modification, import of the snRNP core, or assembly of the spliceosome itself. Despite more than two decades of research, some of the functions of the SMN complex and its particles have not been fully revealed, and thus it is not clear from the cell to what extent this complex influences not only snRNP biogenesis but also the entire spliceosome. The aim of this work, according to the available research, is to describe the SMN complex in more depth and to understand its functions in snRNP particle biogenesis. Key words: SMN complex, snRNP, snRNA, Sm protein, spliceosome
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Optimization of dynamic headspace and thermal desorption parameters for introduction of human scent volatile samples into GCxGC-TOFMS
Růžková, Lucie ; Kyjaková, Pavlína (advisor) ; Sobotníková, Jana (referee)
Comprehensive two-dimensional gas chromatography has become one of the most widely used methods for the analysis of human odor, which enables better separation of substances from the sample compared to classical gas chromatography. Dynamic headspace (DHS) with thermal desorption is often used for the transfer of human body odor analytes from the sampling sorbent to the gas chromatograph. The aim of this work was to optimize the parameters of DHS for human body odor samples and two-dimensional gas chromatography. Two parameters of the DHS were chosen for the optimization, namely the volume and flow rate of the inert gas that carries the sample onto the sorbent. A total of 16 settings of these parameters were selected and used to measure samples containing a piece of cotton and a model mixture. The model mixture was prepared to mimic the best the composition of human body odor in terms of polarities and boiling points of the compounds contained in it. The obtained peak areas of the analytes from the model mixture were compared and the most suitable setting of the DHS parameters was found. This setting was tested on a real human odor sample. Keywords: Human odor, GC×GC-TOFMS, dynamic headspace, thermal desorption, model mixture
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The role of CKAP5 in mediating crosstalk between actin and microtubule cytoskeleton
Dujava Ždímalová, Michaela ; Lánský, Zdeněk (advisor) ; Middelkoop, Teije Corneel (referee)
Dynamic changes in cytoskeletal architecture are essential for many crucial events throughout lives of all cells. One of the examples is neuronal pathfinding, ensured by specialized axonal structures enriched in actin and microtubule cytoskeleton, known as neuronal growth cones. Growth cones act as motile sensors and navigators, as the tight regulation of their actin and microtubule cytoskeleton results in directed axonal outgrowth guided towards the proper targets, which is crucial for processes such as synaptogegnesis or regeneration. Recently, protein CKAP5 (previously described as a microtubule + tip polymerase) has been proposed to facilitate actin-microtubule crosstalk in growth cones, indispensable for their proper functioning. Here, we combine the power of in vitro reconstitution assays with total internal reflection fluorescence microscopy to explore the underlying mechanism of CKAP5 actions. Our findings confirm that CKAP5 also associates with actin filaments and indeed, recruits them to the microtubule lattice. Furthermore, we describe a remarkable behavior of dynamic system containing CKAP5 and both, microtubules and actin filaments, wherein actin bundles are templated along dynamic microtubules by CKAP5. Importantly, upon microtubule depolymerization, the corresponding actin bundle can...
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High dynamic range rendering of virtual 3D scenes
Goncearenco, Vadim ; Chlubna, Tomáš (referee) ; Pečiva, Jan (advisor)
Tato bakalářská práce je zaměřena na téma Vysokého Dynamického Rozsahu (HDR), konkrétně různých HDR technik, které jsou široce používány v oblasti počítačové grafiky. Navíc se zabývá Vulkan API a jeho aplikací pro HDR vykreslováni virtuálních 3D scén. Praktická část této práce je aplikace pro renderování 3D scén, jejímž účelem je demonstrovat praktickou implementaci popsaných HDR technik, jako jsou globální operátory mapování tónu (fotografické, filmové a založené na ACES), lokální operátor mapování tónu založený na bilaterálním filtru, dynamická adaptace oka, exposure fusion a pokročilý bloom efekt.
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Methods for Playing the Game 'Liar's Dice' Using Dynamic Programming
Lohn, Marek ; Šátek, Václav (referee) ; Zbořil, František (advisor)
This project is about Methods of playing game Liar’s Dice using dynamic programming. The algorithm that was chosen for my study is SARSA, short for State Action Reward State Action algorithm. It is a modified version of algorithm named Q-Learning. It comparing algorithm SARSA with other algorithms by letting them play against each other in application, that was made in Unity Engine. Algorithms that were compared to SARSA are Q-Learning and Counterfactual Regret Minimization. SARSA achieved a 69,147 % win ratio in a game against Q-Learning. In games against Counterfactual Regret Minimization it was only 25 % win ratio. The main outcome of this study is that modified SARSA is effective against Q-Learning algorithm in a game of Liar’s Dice. On the other hand the SARSA algorithm was very ineffective against the Counterfactual Regret Minimization algorithm.
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Model of the oscillating system with kinematic excitation
Vrzal, Vojtěch ; Radil, Filip (referee) ; Formánek, Martin (advisor)
This bachelor thesis deals with the design and implementation of an oscillation model of a system with kinematic excitation. The aim of the thesis was to create a prototype that would simulate the behaviour of the dynamic system as closely as possible and would allow its behaviour to be analysed and subsequently used as a teaching model. In the research part, the system equations and the state-space model are derived. Subsequently, the structure including actuator and sensors is designed and fabricated. Finally, the system parameters for the mathematical model are estimated and then compared with the measured data.
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Using of Perovskite Nanoparticles in Biochemistry
Srncová, Melanie ; Tumová, Šárka (referee) ; Pospíšil, Jan (advisor)
This bachelor's thesis examines study of the properties of lead halide perovskite nanoparticles and their use in biochemistry. The synthesis of two types of perovskite nanoparticles MAPbBr3 and MAPbCl3 was performed using the LARP method. During the synthesis was observed the influence of the mixing length of the precursors on the properties of these solutions, which were characterized using UV-VIS spectrophotometry, fluorescence spectrometry and dynamic light scattering. A discussion of the obtained results was carried out along with a discussion of the suitability of using these perovskite nanoparticles in biochemistry due to the toxicity of the lead that these nanoparticles contain.
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Design and production of pendulum tuned mass damper
Čupr, Michal ; Rubeš, Ondřej (referee) ; Kšica, Filip (advisor)
In a real environment, various external conditions can cause vibration of the machines, buildings or other systems. To prevent vibration of the system with low frequencies, pendulum tuned mass damper can be installed. The first part of this thesis describes the oscillation of simple structures for systems with one or two degrees of freedom. This analysis is then applied to mechanism that contains pendulum tuned mass damper. The damper’s principle is explained along with its important parameters and properties. Design and tuning of the damper are explained. Text continues with description of several types of the damper and there are mentioned some examples of their applications. In the final part, a model of the mechanism with pendulum tuned mass damper is designed and it is described mathematically using programs Matlab and Ansys. Subsequently, the model was made and the real model was compared with mathematical model. It was found that effectiveness of the damper depends most on the natural frequency of the system and the dissipation energy from it. The manufactured pendulum damper effectively dampens the oscillation of the real model, and the course of its oscillations corresponds to the mathematical model.
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